柴油机的燃烧和排放与其喷雾特性有着密切的关系，研究喷雾特性的影响因素和变化规律，探明喷雾与空气的混合过程及蒸发过程，合理地组织燃烧，对提高柴油机的性能是至关重要的。本文结合作者的科研工作，对柴油机缸内喷雾浓度分布的各种诊断技术，进行了详细的论述，指出了各种诊断技术的优点及其局限性，对几种有前途的测试技术给予了重点介绍。 The combustion and emission of diesel engine are closely related to the spray characteristics. Studying the influencing factors and variation rules of the spray characteristics, finding out the mixing process and evaporation process of the spray and air, and organizing the combustion reasonably are essential to improve the performance of the diesel engine . In this paper, the author’s research work, the distribution of diesel cylinder spray concentration of various diagnostic techniques were discussed in detail, pointed out the advantages of various diagnostic techniques and limitations of several promising testing techniques to give the key Introduction.